Thanks for the help! I've altered it and now it prints all the events
lyr = "Heatmap_Filtered"
events = arcpy.da.SearchCursor(lyr, ['Event'])
unique_events = list(set([row[0] for row in events]))
unique_events
print(unique_events)
Where I'm having problem with now is creating the SQL using AddField Delmiters. Where is FC located?
where_clause = """ {0} = '{1}' """.format(arcpy.AddFieldDelimiters(fc, 'Heatmap_Filtered'), 'Unique_events')
Then I'd assume I'd just drop the sql expression in select by attribute?
arcpy.management.SelectLayerByAttribute("RTL", "NEW_SELECTION", "Event” “sql_exp”)